It's a sellout. But how much of a home-field advantage will it really be for the Lions on Sunday, as Steeler Nation invades Ford Field, the site of Pittsburgh's Super Bowl XL triumph in February 2006.

The Lions' last home game was a noisy success, with barely 40,000 fans on hand to see the home team end its 19-game losing streak with a win over the Washington Redskins. A few days later, coach Jim Schwartz taped a thank-you phone message that was delivered to season-ticket holders.

"Thanks again for all your support," Schwartz said at the end of the message. "We need your passion and energy at every home game. You really do make a difference. And remember, when we win, we win together."

Schwartz was asked Friday, though, if he thought the Lions' fans could duplicate their last performance, or whether they'd be drowned out by a sea of black and gold.

"Oh, I know our fans will be much louder than any Pittsburgh fans that'll show up," Schwartz said. "I think anybody wants to support a winner. At the end of that (Washington) game, I mean, that was a fun game to coach, a fun game to play, a fun game to be a fan at. And when that crowd was going in the fourth quarter, particularly the last drive, you know, I'm not the ticket man -- I don't know how many people were in the stands -- but it sounded like it was 100,000 in there. And it made a difference. I think they had a good time and that'll carry over to future games."

In the stadium or at home, here's five storylines to watch Sunday:
Daunte-ing assignment?

With Matthew Stafford (knee) missing most of the practice time this week, Daunte Culpepper is expected to get the start at quarterback.

The veteran called that possibility a "great opportunity" on Friday. Others might compare it to losing a bet, given the kind of pressure and problems the Steelers can create defensively. Dick Lebeau's defense -- a base 3-4 unit that blitzes from all angles -- ranks third in the NFL against the run while allowing less than 6 yards per passing attempt.

Culpepper, in his 11th NFL season, actually has faced the Steelers only once before in the regular season -- a December 2001 loss in which he was forced to leave the game late with a knee injury. But he spent the week watching plenty of game film of the defending Super Bowl champs.

"They're a very physical team," said Culpepper, who was 6-of-11 for 54 yards in fourth-quarter relief duty last week at Chicago. "And on top of that, they have great schemes. They mix it up a lot. They never do the same things play after play. You might get a base defense this time, the next time you get some exotic blitz, and they've been very good at it over the years. They're good at it now. They're the world champions. So we've got to be on top of our game."
Growing pains

Safety Louis Delmas was named NFL's defensive rookie of the month for September. But "rookie" is the operative word there, as his coaches are quick to point out. The Lions' second-round pick has made some big plays as starter since Day 1. But he has made his share of mistakes as well. One five-play stretch in Sunday's loss at Chicago began with Delmas talking trash on the Bears' sideline after the Lions gave up a 43-yard kickoff return and ended with a glaring missed tackle on Matt Forte's 37-yard touchdown run.

"He's still not the pro that he should be," defensive coordinator Gunther Cunningham said. "I think there's some immaturity in him. And it causes him to get in trouble. It's not lack of enthusiasm. It's too much enthusiasm. And what he doesn't realize is, this isn't college football. Those guys on the other side are pretty good. And they like playing against rookies, and I think he got his eyes opened. He's been a lot more about business since the (Chicago) game."

Delmas won't argue with that, and Sunday against the Steelers he'll get another chance to prove he's learning.

"The main thing I need to be focused on is being consistent with my tackling and play reads," Delmas said. "In college, I got away with it just because my athletic ability was able to take over, but here everyone is equal, if not better. I need to be more consistent and execute my plays."
Big problem

Ben Roethlisberger fairly cringes as he recalls his first visit to Ford Field a few years ago, even though it ended with a Super Bowl XL victory over Seattle for the Steelers' second-year quarterback. Admittedly nervous from start to finish, Roethlisberger was 9-for-23 for 123 yards with two interceptions against the Seahawks that night, and he says now he "almost helped us lose it."

But he didn't, and that was only the beginning of what has become one of the most successful young careers of any quarterback in NFL history. His 51 regular-season wins entering 2009 were the most ever for a starting quarterback after five seasons in the league. His .718 winning percentage (61-24, including 8-2 in the playoffs) and 63.2-percent career completion rate are franchise bests.

This season, he's leading the NFL in completion percentage (73.2) and boasts a 98.1 passer rating. And now that he's added a pump-fake to his routine, the Steelers are getting even more big plays in the passing game, averaging 8.4 yards per attempt.

Roethlisberger's size and strength at 6-foot-5 and 240 pounds -- and his ability to feel the rush and buy time with his surprising mobility -- presents a huge challenge for any defense. And at his best, Big Ben is a gamer, playing through pain -- as he did in winning a second Super Bowl title back in February -- and making plays, with 16 fourth-quarter comebacks already.
Return to sender

Everyone else has had their turn. Now it's Derrick Williams' chance to show what he can do in the regular season, replacing fellow rookie Aaron Brown as the No. 1 kickoff returner. Williams, who struggled with fumbles on punt returns throughout training camp and the preseason, was inactive for three of the Lions' first four games.

"The only time I haven't played -- ever -- was when I broke my arm my freshman year in college," said Williams, a third-round draft pick as a receiver and return specialist. "So I'm excited to get out there. I'm just gonna try to do as much as I can to help the team win.

"I've been waiting for an opportunity to go out and show what I can do and make some smart plays. I think I did a good job in the preseason as a receiver, but not really showing what I could do as a return man."

For all the concerns about the Lions' coverage units -- and they'll be tested again by the Steelers on Sunday -- the return game was supposed to be greatly improved this season Dennis Northcutt has had limited opportunities on punt returns thus far. But Brown did get off to an impressive start, providing a spark in the return game at New Orleans in the opener. Since then, though, he'd averaged just 17.7 yards per return, and last week he muffed two first-half returns.

"First things first, on punt and kickoff returns, you've gotta secure the ball," special teams coordinator Stan Kwan said. "If you don't have the ball, you have nothing."
When the Levy breaks

Gunther Cunningham is convinced rookie linebacker DeAndre Levy has earned a full-time starting job. But at the expense of whom?

Levy made an impressive starting debut in place of an injured Ernie Sims in the win over Washington two weeks ago. Sims returned to the starting lineup last week at Chicago, but he was ineffective again before aggravating his right shoulder injury in the second half against the Bears.

"And he didn't play well before that (at Chicago)," Cunningham said. "He was in the right positions, but he didn't make any plays, which was really disappointing. Then he got banged up again, and there's so much 'want-to' in him, my worry is I don't know how bad this (injury) is."

It doesn't appear to be bad enough to keep Sims out of uniform -- he's officially listed as probable for Sunday's game against the Steelers. But expect more of Levy, either at weakside linebacker in place of Sims or on the strong side in place of Julian Peterson, whose part-time role as a defensive end continues to expand. Outside linebacker Jordon Dizon also plays a role in nickel-defense situations.

"The good thing about those guys is we have a couple multidimensional players -- guys that can play nickel, that can rush, that can play linebacker," coach Jim Schwartz said. "We can go a lot of different directions there, and we'll probably stay with what we were doing before, where we were rotating through four or maybe five guys."